Various designs of condenser and cooling systems exist in the field of energy generation by steam turbines. However, it has become increasingly important to improve efficiency in order to conserve fuel and resources.
The traditional steam cycle uses high-energy steam to operate turbines or auxiliary equipment and exhausts the steam into a condenser. In thermal power plants, a steam generator creates steam, which is sent to a turbine. The steam turbine converts the heat in the steam to mechanical power. Any remaining steam is exhausted. A condenser condenses the exhaust steam from a steam turbine by using a cooling medium such as water or air. The condensed water is known as condensate. The condensate can either be considered waste or be reused in a steam generator. This process of cooling is known as subcooling.
If reused, a condensate pump pumps the condensate to a feed pump. The feed pump then pumps the condensate to the steam generator so that the condensate can be reheated and turned to steam for use again in the turbine.
Previous attempts at increasing efficiency have failed due to the problem of subcooling the exhaust steam. Subcooling is required to allow the condensate pumps to pump the water forward without cavitation. In addition, subcooling increases the efficiency of the turbines. However, each degree that the steam and condensate is cooled is heat energy that must be put back into the condensate to convert it back into steam. Thus, excessive subcooling actually decreases the efficiency of the steam cycle.
With the forgoing problems and concerns in mind, it is the general object of the present invention to provide a combined circulation condenser, which overcomes the above-described drawbacks while increasing the efficiency of the turbine and steam cycle.